Smart Machine Smart Decision
SIM868_Series_Hardware_Design_V1.06 2 2017-07-13
Contents
1.
Introduction ........................................................................................................ 10
2. SIM868 Overview .............................................................................................. 10
2.1. SIM868 Key Features ......................................................................................................... 11
2.2. Operating Modes ................................................................................................................. 14
2.3. Functional Diagram............................................................................................................. 15
3. Package Information ......................................................................................... 16
3.1. Pin Out Diagram ................................................................................................................. 16
3.2. Pin Description .................................................................................................................... 17
3.3. Package Dimensions ........................................................................................................... 19
4. Application Modes of SIM868 .......................................................................... 22
4.1. All-in-one Mode .................................................................................................................. 22
4.2. Stand-alone Mode ............................................................................................................... 23
5. Application Interface of GSM .......................................................................... 24
5.1. Power Supply of GSM ........................................................................................................ 24
5.2. Reference Circuit of GSM Power Supply ........................................................................... 25
5.3. Power on/off GSM Part ....................................................................................................... 26
5.3.1. Power on GSM .................................................................................................................................... 26
5.3.2. Power off GSM ................................................................................................................................... 27
5.4. Power Saving Mode of GSM .............................................................................................. 28
5.4.1. Minimum Functionality Mode of GSM Part ....................................................................................... 28
5.5. Serial Port of GSM .............................................................................................................. 29
5.5.1. Function of Serial Port ........................................................................................................................ 30
5.5.2. Serial Interfaces ................................................................................................................................... 30
5.5.3. Debug Interface ................................................................................................................................... 32
5.5.4. Software Upgrade of GSM .................................................................................................................. 33
5.6. UART1_RI Behaviors ......................................................................................................... 33
5.7. Audio Interfaces .................................................................................................................. 34
5.7.1. Speaker Interfaces Configuration ........................................................................................................ 35
5.7.2. Microphone Interfaces Configuration ................................................................................................. 36
5.7.3. Audio Electronic Characteristic .......................................................................................................... 36
5.7.4. TDD Noise of GSM ............................................................................................................................ 36
5.8. SIM Card Interface.............................................................................................................. 37
5.8.1. SIM Card Application ......................................................................................................................... 37
5.8.2. SIM Card Design Guide ...................................................................................................................... 38
5.8.3. Design Considerations for SIM Card Holder ...................................................................................... 39
5.9. SD Interface ........................................................................................................................ 41
5.10. I2C Bus ............................................................................................................................... 41
5.11. ADC .................................................................................................................................... 41